The engine in my '94 STS makes a ticking sound during medium to hard acceleration. I suspect it is an exhaust leak. How hard is it to get to the exaust manifolds on the N*? I can't even see them from above the engine and I haven't tried looking from under the car. Is it a major operation to replace the gaskets? I have a feeling it won't be as easy as working on my '70 Mustang. I appreciate any help or advise.